Thread: Fixing HDs?
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Old 24th June, 2002, 02:54 PM
Aedan Aedan is offline
Chief Systems Administrator
Join Date: September 2001
Location: Europe
Posts: 13,075

There's two levels of "bad sector". The OS keeps a map of sectors it believes are bad. Of course, this "bad" table can be manipulated to hide information, and just generally be a pain in the backside.

On the other hand, most IDE drives have a remap table, which has a mapping from a genuine bad sector to a spare sector. Only the HDD itself knows which sectors are bad, and which are good.

There are programs that can address the drive below the file system level. These can be used to clear file system level "bad sector" markers. Some of them are effective enough to write various patterns across the disk in an attempt to test each and every sector accessable.

IBM's Drive Fitness Test (DFT) is capable of doing this. Some of the tests will run happily on a non-IBM drive.

Any views, thoughts and opinions are entirely my own. They don't necessarily represent those of my employer (BlackBerry).

Last edited by Áedán; 24th June, 2002 at 04:42 PM.
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